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The SOFC interconnect materials La${}_{0.75}$Sr${}_{0.25}$Cr${}_{1-x}$O${}_{3-\delta }$$(x=0$–$0.04)$ were prepared using an auto-ignition process. The influences of Cr deficiency on their sintering, thermal expansion and electrical properties were investigated. All the samples were pure perovskite phase after sintering at 1400${}^{\circ }$C for 4 h. The cell volume of La${}_{0.75}$Sr${}_{0.25}$Cr${}_{1-x}$O${}_{3-\delta }$ decreased with increasing Cr deficient content. The relative density of the sintered bulk samples increased from 93.2% $(x=0)$ to a maximum value of 94.7% $(x=0.02)$ and then decreased to 87.7% $(x=0.04)$. The thermal expansion coefficients of the sintered bulk samples were in the range of $10.60$–$10.98\times 10^{-6}{\mathrm{\text{K}}}^{-1}$ (30–1000${}^{\circ }$C), which are compatible with that of YSZ. Among the investigated samples, the sample with 0.02 Cr deficiency had a maximum conductivity of 40.4 Scm${}^{-1}$ and the lowest Seebeck coefficient of 154.8 $\mu$VK${}^{-1}$ at 850${}^{\circ }$C in pure He. The experimental results indicate that La${}_{0.75}$Sr${}_{0.25}$Cr${}_{0.98}$O${}_{3-\delta }$ has the best properties and is much suitable for SOFC interconnect material application.

The ceramics with the composition of $x{\mathrm{\text{Na}}}_{0.5}{\mathrm{\text{Bi}}}_{0.5}{\mathrm{\text{TiO}}}_3$–$(1-x){\mathrm{\text{Ba}}}_{0.66}{\mathrm{\text{Mg}}}_{0.04}{\mathrm{\text{Sr}}}_{0.3}{\mathrm{\text{TiO}}}_3$ (NBT–BMST) in which $x$ = 0.2, 0.3, 0.4 and 0.5 were prepared successfully by the solid-state reaction method. The effects of NBT-doping on phase structure, morphology, temperature stability and dielectric properties had been investigated in detail. The XRD results show that the composites are composed of tetragonal perovskite. The phase structure of NBT–BMST is observed by scanning electron microscopy. The dielectric constant of $0.3{\mathrm{\text{Na}}}_{0.5}{\mathrm{\text{Bi}}}_{0.5}{\mathrm{\text{TiO}}}_3$–$0.7{\mathrm{\text{Ba}}}_{0.66}{\mathrm{\text{Mg}}}_{0.04}{\mathrm{\text{Sr}}}_{0.3}{\mathrm{\text{TiO}}}_3$ ceramic is $\sim$4100, the temperature coefficients of capacitance are −15%, 15% and 22% at −55${}^{\circ }$C, 60${}^{\circ }$C and 200${}^{\circ }$C, respectively. And the dielectric loss is less than 0.13, which is obviously superior to other compositions. The results of this work showed that the component of $0.3{\mathrm{\text{Na}}}_{0.5}{\mathrm{\text{Bi}}}_{0.5}{\mathrm{\text{TiO}}}_3$–$0.7{\mathrm{\text{Ba}}}_{0.66}{\mathrm{\text{Mg}}}_{0.04}{\mathrm{\text{Sr}}}_{0.3}{\mathrm{\text{TiO}}}_3$ is a promising candidate to high-temperature stable materials.

Microstructures, electrical transport and magnetic properties of Sr${}_2$Ti${}_{1-x}$Co${}_x$O${}_4(0\le x\le 0.3)$ ceramics are investigated. With Co doping, the Sr${}_2$Ti${}_{1-x}$Co${}_x$O${}_4$ ceramics remain tetragonal structure while the grain size is decreased with doping. Magnetic moment is enhanced with Co doping and ferromagnetism is observed at low temperatures for Co-doped Sr${}_2$TiO${}_4$. The Sr${}_2$Ti${}_{0.9}$Co${}_{0.1}$O${}_4$ and Sr${}_2$Ti${}_{0.7}$Co${}_{0.3}$O${}_4$ show semiconductor-like transport properties, which can be well fitted by Mott variable range hopping model. The results will provide an effective route to synthesize Sr${}_2$Ti${}_{1-x}$Co${}_x$O${}_4$ ceramics as well as to investigate the physical properties.

X-ray Computed Tomography (CT) is a powerful non-destructive technique that can yield interesting structural information not discernible through visual examination only. This paper presents the results of the CT scans of four objects belonging to the Romanian cultural heritage attributed to the Vinča, Cucuteni and Cruceni-Belegiš cultures. The study was performed with an X-ray tomographic device developed at the Department for Applied Nuclear Physics from Horia Hulubei National Institute for Nuclear Physics and Engineering in Măgurele, Romania. This apparatus was specially designed for archaeometric studies of low-Z artifacts: ceramic, wood, bone. The tomographic investigations revealed the internal configuration of the objects and provided information about the degree to which the previous manipulations affected the archaeological items. Based on the X-ray images resulting from the CT scans, hints about the techniques used in the manufacturing of the artifacts were obtained, as well as some indications useful for conservation/restoration purposes.